Use the NativeTheme to create the text color for text during the generated card animation.

chrome/browser/ui/views/autofill/autofill_dialog_views.cc

Index: chrome/browser/ui/views/autofill/autofill_dialog_views.cc
diff --git a/chrome/browser/ui/views/autofill/autofill_dialog_views.cc b/chrome/browser/ui/views/autofill/autofill_dialog_views.cc
index 64cdc04ed63cc020151b1ca1b0341054cbb538e3..7f979d4316fb50974ac31416f7471a7e4c65e039 100644
--- a/chrome/browser/ui/views/autofill/autofill_dialog_views.cc
+++ b/chrome/browser/ui/views/autofill/autofill_dialog_views.cc
@@ -35,6 +35,7 @@
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/animation/animation_delegate.h"
 #include "ui/gfx/canvas.h"
+#include "ui/gfx/color_utils.h"
 #include "ui/gfx/path.h"
 #include "ui/gfx/point.h"
 #include "ui/gfx/skia_util.h"
@@ -578,7 +579,8 @@ int AutofillDialogViews::OverlayView::GetHeightForContentsForWidth(int width) {
 }
 
 void AutofillDialogViews::OverlayView::UpdateState() {
-  const DialogOverlayState& state = delegate_->GetDialogOverlay();
+  const DialogOverlayState& state =
+      delegate_->GetDialogOverlay(GetNativeTheme());
 
   if (state.image.IsEmpty()) {
     SetVisible(false);
@@ -654,10 +656,19 @@ void AutofillDialogViews::OverlayView::OnPaint(gfx::Canvas* canvas) {
     arrow.close();
 
     SkPaint paint;
-    paint.setColor(kShadingColor);
+    SkColor background_color = background()->get_color();
+    int background_luminance = color_utils::GetLuminanceForColor(background_color);
+    int background_alpha = static_cast<int>(
+        7 - 15 * (background_luminance - 255) / 255);

[groby-ooo-7-16, 2013/12/10 20:26:49]

So we get a negative alpha for high-luma backgrounds? Doesn't the
BlendTowardOppositeLuminance function already take care of biasing?

[Sheridan Rawlins, 2013/12/10 20:51:56]

No, alpha is always positive - the luminance returned in
color_utils::GetLuminanceForColor is 0..255, but I could just switch it around
and make it positive if that's easier to understand.

BlendTowardOppositeLuminance only takes the direction into account, blending
white into a darker color or black into a lighter color; it doesn't take human
perception/bias into account.

+    int subtle_border_alpha = static_cast<int>(
+        10 - 20 * (background_luminance - 255) / 255);
+
+    paint.setColor(color_utils::BlendTowardOppositeLuminance(
+        background_color, background_alpha));
     paint.setStyle(SkPaint::kFill_Style);
     canvas->DrawPath(arrow, paint);
-    paint.setColor(kSubtleBorderColor);
+    paint.setColor(color_utils::BlendTowardOppositeLuminance(
+        background_color, subtle_border_alpha));
     paint.setStyle(SkPaint::kStroke_Style);
     canvas->DrawPath(arrow, paint);
   }